Leading this subterranean existence, and generally thought unworthy the notice of educated people, they naturally underwent repeated changes; so that we have numerous versions of the same story, and incidents, descriptions, and entire stanzas are borrowed and lent freely among the different ballads. The circumstance, e.g., of the birk and the briar springing from the graves of true lovers and intertwisting their branches occurs in the ballads of “Fair Margaret and Sweet William,” “Lord Thomas and Fair Annet,” “Lord Lovel,” “Fair Janet,” and many others. The knight who was carried to fairyland through an entrance in a green hillside, and abode seven years with the queen of fairy, recurs in “Tam Lin,” “Thomas Rymer,"[3] etc. Like all folk-songs, these ballads are anonymous and may be regarded not as the composition of any one poet, but as the property, and in a sense the work, of the people as a whole. Coming out of an uncertain past, based on some dark legend of heart-break or blood-shed, they bear no author’s name, but are ferae naturae and have the flavor of wild game. They were common stock, like the national speech; everyone could contribute toward them: generations of nameless poets, minstrels, ballad-singers modernized their language to suit new times, altered their dialect to suit new places, accommodated their details to different audiences, English or Scotch, and in every way that they thought fit added, retrenched, corrupted, improved, and passed them on.